What is the biggest 5 digit number such that when multiplied by a single digit, the result is a six digit number, with all digits identical?
(In reply to
Solution (spoiler) by Steve Herman)
Your answer is the same as I found.
95238 * 7 = 666666
Given the difficulty level it must be assumed the numbers are base10 composed of decimal digits. If a broader assumption is made, one can find "bigger" 5 digit numbers. I.e., in base 12, B2796 * 7 = 666666; and
B2796_{12} = 232674_{10 }> 95238_{10}.
As there is are limits of 5 digits multiplied by 1 digit to equal a 6 digit repdigit number, and if limited to a maximum base of 36, there must be a definite largest number that exists. This problem of course would not be a difficulty 1 level problem (except that one could use a computer program to solve it almost as easy).
Edited on June 13, 2012, 11:48 pm

Posted by Dej Mar
on 20120611 22:51:30 